Which statement is true about the capabilities of a voice gateway router？（）A、voice gateways with analog interfaces need a gatekeeper to convert analog signals into digital format before voice is encapsulated into IP packetsB、voice gateways need a gatekeep

第1题：

When analog signals are digitized using the G.711 codec， voice samples are encapsulated into protocol data units （PDUs） involving which three headers？ （）

• A、IP
• B、TCP
• C、RTP
• D、UDP
• E、H323
• F、CRTP

第2题：

Which two statements are true about analog to digital conversion of voice signals for use in digital telephony networks？（）

• A、The three required steps in the analog to digital conversion are sampling，encoding，and compression.
• B、The three required steps in the analog to digital conversion are sampling，quantization，and compression.
• C、The three required steps in the analog to digital conversion are sampling，quantization，and encoding.
• D、The output of the sampling process is a pulse code modulation （PCM） signal.
• E、The output of the sampling process is a pulse amplitude modulation （PAM） signal.

第3题：

第4题：

Which two statements are true about voice ports on a router？ （）

• A、 Calls to the PSTN can be made via the use of FXO or T1/E1 trunk ports.
• B、 Calls to the PSTN can be made via FXS or T1/E1 trunk ports.
• C、 Analog and IP phones can be connected to the VoIP network via FXO or T1/E1 trunk ports.
• D、 Calls between analog phones that are attached to the FXS ports in a VoIP network can be completely processed by voice-enabled routers.

第5题：

Which IP telephony component provides call processing, such as signaling, that in a traditional voice network is provided by switching equipment, such as a PBX?（）

• A、Client-based software, such as CiscoSoftPhone
• B、Voice gateways, such as the Cisco VG248 Analog Phone Gateway
• C、Call-management hardware and software, such as CiscoCallManager
• D、Advanced call-handling software, such as Cisco Unity

第6题：

Which two VoIP capabilities are utilized when the CallManager and the gateway are configured for Survivable Remote Site Telephony？（）

• A、 Analog phones， connected to the PSTN， act as internal call agents if IP communication to the CallManager is lost.
• B、 An onsite gateway reroutes calls over the PSTN if IP communication to the CallManager is lost.
• C、 The IP phones can reroute calls over the PSTN if IP communication to the CallManager is lost.
• D、 Local voice gateways can assume the function of a call agent if IP communication to the CallManager is lost.
• E、 IP phones use an internal call agent if IP communication to the CallManager is lost.

第7题：

Which IP telephony component provides call processing, such as signaling, that in a traditional voice network is provided by switching equipment, such as a PBX?（）

• A、Advanced call-handling software, such as Cisco Unity
• B、Call-management hardware and software, such as CiscoCallManager
• C、Client-based software, such as CiscoSoftPhone
• D、Voice gateways, such as the Cisco VG248 Analog Phone Gateway

第8题：

Which two statements about voice VLANs are correct？（）

• A、Voice VLANs eliminate the need for QoS configuration
• B、Voice VLANs are used on trunk links to eliminate the need for QoS CoS markings
• C、Voice VLANs are mainly used to reduce the number of access switch ports that are used in the network
• D、Voice VLANs can be configured to forward existing CoS priorities or override them
• E、Voice VLANs are mainly used between access layer switches and distribution layer switches
• F、Voice VLANs can be configured on Layer 2 ports only

第9题：

Which statement is true about the comparison of voice traffic with video traffic？（）

• A、 Video conferencing traffic tends to be much more bursty in nature and is more prone to have an impact on other traffic flows.
• B、 Latency requirements are less stringent for video traffic than for voice traffic.
• C、 Video traffic is less sensitive to dropped packets than for voice traffic.
• D、 Video traffic requires the retransmission capabilities of TCP whereas voice uses UDP.
• E、 Voice traffic tends to be much more bursty in nature and is more prone to have an impact on other traffic flows.
• F、 Voice traffic requires the retransmission capabilities of TCP whereas video uses UDP.

第10题：

Which three functions are associated with a Cisco Unified CallManager？ （）

• A、 connects traditional telephony devices to voice over IP infrastructure
• B、 converts analog signals to digital format
• C、 performs voice compression
• D、 performs call processing
• E、 performs dial plan administration
• F、 performs signaling and device control